Racal-Dana 1992 Nanosecond Universal Counter

I recently purchased a Racal-Dana 1992 Counter off eBay for a bit more than I wanted to spend, and figured when I got it, it would be non-functional. But, when it arrived, it was fully functional, albeit with the same mushy buttons that everyone complains about with these older units. Turns out Racal-Dana used a molded rubber for the “spring” of the button, which over time decomposed/cracked and left the user with buttons that didn’t really spring.

The common fix is to use more modern buttons and solder those in, then modify the keys to fit on round button actuators vs the cross-top ones that are stock. I’ll post a new article about that fix once I buy the buttons (waiting for other stuff to order from Digi-key/Mouser).

The unit also came with an oven stabilized clock (OCXO), and the battery module (which is Lead-Acid, and added a good 2-3kg to the weight of the unit). The OCXO seems to be quit good, and after a day or two of letting the unit sit in standby, there was no change at all during that time. To further calibrate, I’d need a rubidium standard. But, I should be able to calibrate my TG1000 with it, no problem (it appears to be out by about 2Hz at 10Mhz. So, not bad. =)

The battery option, on the other hand, is seemingly bad. While I’m sure the charging board is fine (supplies about 7.4V to each battery set in standby), the battery doesn’t seem to charge (and therefore, function). I think I’m going to try linking the two 3 cell packs together, and hooking it up to a Battery Tender (or the like) to see if I can resurrect it. I’m guessing it’s either just completely sulfonated, or something else. Will certainly update if I get it back to life.

With the battery in the unit, it is quite heavy (about 15lbs (~7KG)). If I can’t get the battery functional, I’ll just remove it and save my bench shelf some load.

Given my minimal use of the unit so far, I’m quite happy. While I paid a bit more than I wanted to1, I think it will serve me for some time as a very capable counter. I may also, at some point, replace the OCXO with the Gerry Sweeney mod but at this point, the OCXO seems very capable for my needs2.

The unit makes a very useful addition to my bench of older test gear (most dating from the mid-80’s to mid-90’s, save my scope). I think I’ll also be able to loan it to any HAM operators I know should they need to check their radio calibration as well. =) Only negative about the unit is the funky switches Racal-Dana used. But, I’ll get them replaced here in the not-so-distant future.

Rating:

I was bidding on it, and at the last second meant to increase my bid to $85, but instead did $585, which won me it for $91… at least someone didn’t bid $200 [↩]

Gerry modded his because he had the standard oscillator, which is several orders of magnitude worse than the OCXO that came with mine [↩]